Regulator for dynamo-electric machines



(No Model.)

T. A. EDISON.

I REGULATOR FOR DYNAMO ELEGTRIO MACHINES. No. 265,780. Patented Oct. 10,1882.

WITNESSES i INVENTOR! UNITED STATES PATENT ()FFICE.

THOMAS A. EDISON, OF MENLO PARK, NEIV JERSEY.

REGULATOR FOR DYNAMO-ELECTRIC MACHINES.

SPECIFICATION forming part of Letters Patent No. 265,780, dated October10, 1882.

Application filed August 7, 1882.

T 0 all whom it may concern:

Be it known that I, THOMAS A. Enrson, of Menlo Park, in the county ofMiddlesex and State of New Jersey, have invented a new and usefulImprovement in Regulating the Generative Capacity of Dynamo or MagnetoElectric Machines, (Case No. 402;) and I do hereby declare that thefollowingis at'ull and exact description of the same, reference beinghad to the accompanying drawing, and to the letters of reference markedthereon.

The object of my invention is to produce means for regulating thegeneration of current by a dynamo or magneto electric machine supplyinga multiple-arc system of electrical dis tribution which shall be causedto operate by the thermal effect of the current generated. To accomplishthis 1 place in one of the conductors of the main circuit a metal stripor bar which will be heated by the passage of current through it. Thisbar is so placed that its expansion and contraction, caused byvariations in such heating, will cause the opening and closing ofcircuits, such opening and closing causing variations in the currentenergizing the field-magnet ofthe generator, the coils of which magnetare preferably included in a multiple-arc circuit or circuits from themain conductors, though, if desired, the magnet may be energized fromany external source.

A convenient form of my invention is one in which a double stripcomposed of two metals of different degrees of expansion is placed inthe main circuit and held rigidly at one end, but free at the other, thecircuit being completed at the free end by means of a point dipping intoa mercury-cup. An arm is attached to the free end of the strip, whicharm carries a number of contact-points, each dipping into a mercury-cup,the contact-points being of different lengths, or the mercury ofdifferent heights, in order that successive contacts may be made andbroken. In the multiple-arc circuit which incrzderthe field-magnetisplaced a series of resistances, around each of which is formed a shuntincluding one of the mercurycups. \Vhen the number of lamps ortranslating devices in multiple-arc on themain conductor is increasedthe increase of current (No model.)

causes the heating of the compound bar, the unequal expansion of whichcauses said bar to bend downward, which lowers the end of the armcarrying the contact-points, which, as they successively dip into themercuziy-cups, cause the closing of the shunts around the resistancesinthelield, and thus increase thegenerative capacity of the machine. At'ecrease in the number of translating devices causes a contrary effect,the sh nut-circuits being opened and the resistances again placed incircuit.

Instead of opening and closing circuits around resistances, thisarrangement may he used to open and close new circuits through the coilsof the fieldanagnet, as shown in (Jase No. 68,618, of even dateherewith, such coils being for this purpose divided into a number ofseparate sections or bobbins each included in a different circuit.

My invention may be more readily understood by reference to the annexeddrawing, which is a diagrammatic view, illustrating the arrangement just described.

A is a dynamo electric machine, and l 2 the main conductors leadingtherefrom, on which are placed in multiple-arc circuits lamps or othertranslating devices, a a a.

3 4: is a multiple-arc circuit energizing the field-magnet of thegenerator and containing resistances R R R B In main conductor l isplaced the compound strip b, at whose free end the point e dips in themercurycup O, and which has secured to it the arm 15, carryingcontact-points c 0, each dipping into a mercurycup, (1, Wires 5 5 fromthe iield-circuit 3 I form shunts around the resistances It R R R.

The operation of these devices is as above described.

What I claim is- I. The combination, with a dynamo or magneto electricmachine and translating devices arranged in multiple are, of aresistance in the field-circuit, mercury-cups connected with suchresistance at intervals, and a thermostatic device in the main circuitcarrying points which dip into said mercury-cups in succession, substantially as set forth.

2. The combination of a multiple-arc circuit including the coils of thefield-magnet of a dy namo-electric machine, a multiple-arc circuitmercury-cups in succession, substantially as 1: including the armatureof said machine, mulset forth.

tipie arc circuits containing lamps or other This specification signedand witnessed this translating devices, (all such multiple-arc cir- 28thday of February, 1882.

euits being derived from the same main conduct0rs,) a resistance in thefield-circuit, mer- THOMAS A. EDISON. cury-cups connected with suchresistance at in- Witnesses: tervals, and a thermostatic device in themain H. \V. SEELY, circuit carrying points which dip into said THOMASJOHNSTON.

